Process of making alloys.



followin ence. especially adapte UNITED STATES PATEnT OFFICE.

ROBERT A. HADFIELD, 0F SHEFFIELD, ENGLAND.

rnocnss or masiinonnnoys.

1,061,373. No Drawing.

Specification of Letters latent. Application filed J uly 5, 1906. Serial No. 324,895.

Patented May 13,1913.

To all whom it may concern:

Be it known that I, Ronanr Anno'rr HAP- FIELD,-8. sub'ect of the Kin of Great Britain, of She eld, England, ave invented a certain new and useful Improvement in Processes of Makin Alloys, of which the is a speci cation. I

In U. Letter Patent No. 745,829 granted to me December 1, 1903, I have set forth an alloy of iron with silicon, or other mater al magnetically equivalent to silicon in the mixture, which is subjected to a described .heat treatment; whereby a magnetic material is produced possessingl magnetic permeability and electric resistance above, and hysteresis uality below, those res ectively of thebest wedish charcoal iron or generall of the purest iron commerciall obtainab oz), and for use in allast coils, transformer plates and like electrical apparatus wherein the reduction of the total magnetic and electric losses to the lowest possible degree is of great importance.

My resent invention is a process of makmg a eye and more particularly such an al oy as described in-tl'ie' foregoing paraaph, whereby improved solidity and omogeneity of structure is obtained.-

The best mode I now know of carrying my said process into effect is as follows I place in any-suitable ladle or other vessel, ferro-silicon containing preferably 50 per cent. of silicon, and raise the same to redheat. In another vessel, I melt pure iron. I pour the molten iron upon ithe red-hot ferro-silicon, thereb producing fusion of the same. The r ting mixture is cast in .ingotsi'n the usualv way.- Just before cast- 5 ing I preferably add a suitable proportion dizer.,

The important feature of my before described processis. the preliminary heating of aluminium, 'or other equivalent dioxiof the ferro-s-ilicon. Inasmuch as this substance fuses at a temperature about {300 to 400 centigrade below that of molten iron, it

is obviousthat the disparity of tempera:

-ture' between redhot ferro-silicon and molten iron is so small that the additional heat units necessary to bring the ferro-sili- 1 con to fluidity are readily communicated to it from the iron itself. wIt is therefore not necessary to raise the iron to a temperature sufficiently high to fuse cold ferro-silicon, which might result in boilin of the iron and consequent impairment 0% the physical properties of the resulting alloy. further advantage depends'upon the fact that the specific gravity of the ferro-silicon is about one uarter less than that of the.

'iron'-so that t e ferro-silicon rises through the fluid iron I poured upon it and disseminates itself through the mass much more rapidly and effectively than if it were added to the molten iron upon the surface of which it would float. The iron-silicon alloy thus sproduced has, as has beenstated, superior ph sical' qualities in solidit and homogeneity, but these may be stlll further improved by the addition of aluminium in proportion not exceedin one percent, just beore the pouring of t e mixture takes place. The aluminium then aacts prom tly upon such'gases as may remain occlu ed in the molten mass and before the latter has op ortunity to absorb impurities which it might not successfully attack.

I claim:

The herein described process of producing a ferro-silicon alloy for magnetic purposes, characterized by 1ts l'ow h steresis andigh magnetic permeability an electric resistance which consists in placing in the ladle ferro-silicon containing about 50% of silicon, raising the ferro-silicon to a red heat, melting pure iron in another vessel, curing the molten iron over the ferro-si icon sothat the ferro-silicon iseasily meltedand disseminates itself through the mass rapidly and effectively and then adding, just before the pouring .of the mixture takes place, alumimum in a proportion not exceeding 1%, then casting into ingots. i In testimony whereof I have signed my.

name hereto in the presence of two witnesses. 95

v ROBERT A. HADFIELD.

f Witnesses:

' Hnnnr E. DIXON,

r Fnenx'Hmson.

A still 

